Replacement tubes for the MT15

[Mikelamury]

I was wondering if it's alright to replace the 5881 tubes in the MT15 JJ6L6GC tubes?

 

[andy474x]

Should be fine, as long as you get the amp biased for the 6L6’s.

 

[bodia]

When did they change to 5881s?

 

[Toolmaster Of Brainerd]

When did they change to 5881s?

The factory that they got their 6L6's from burned down so they had to change. Mark apparently likes the new 5881s better.

 

[bodia]

The factory that they got their 6L6's from burned down so they had to change. Mark apparently likes the new 5881s better.

Got it. I was not aware of that.

 

[Deli6505]

I am tempted to buy one of the newer MT15s just to A/B it with my first gen model. It's always good to have a backup if nothing else.

 

[Sybo]

Q

I am tempted to buy one of the newer MT15s just to A/B it with my first gen model. It's always good to have a backup if nothing else.

Ijust picked one up a couple weeks ago, at GC. How can I tell what version I have. I would also be interested to see about alternative tubes!

 

[Goran Lorencin]

You can have either the 6L6GCs or the 5881s, they are almost the same. You could also put in a pair of KT66s, but ,as I tragically found out, the tube sockets are too close together and the the tubes are practically touching when installed, no bueno.

The MT15 comes from the factory with the 6L6GCs or 5881s, so that means they are both used as the tube that is right for the MT15. Mine came with Ruby 6L6GCs.

 

[Bogner]

The 5881's will traditionally be more dependable. I said "traditionally".

 

[Wyzard]

You can have either the 6L6GCs or the 5881s, they are almost the same.

They're both 6L6s, sure. However:

....traditionally speaking, there have always been practical volume/breakup-related reasons for choosing 5881s over 6L6GCs for live work, especially in what someone much smarter and more experienced than me used to describe as a "musically responsible setting".

IMO, the 5881's sweetness/breakup at (relatively) lesser volumes deserves a much more descriptive comment than "almost the same"

 

[Deleted member 5962]

They're both 6L6s, sure. However:

....traditionally speaking, there have always been practical volume/breakup-related reasons for choosing 5881s over 6L6GCs for live work, especially in what someone much smarter and more experienced than me used to describe as a "musically responsible setting".

IMO, the 5881's sweetness/breakup at (relatively) lesser volumes deserves a much more descriptive comment than "almost the same"

Yes. While in some manners, they are "almost the same," in others, they are pretty different. In the simplest terms, in electrical properties they could be "almost the same" as they are generally interchangeable. But in the finer points, they are more different. Kind of like Rosie O'Donnell and Julie Bowen are almost the same. They are both women. They both live in America. They are both over 45 years old. After that, the differences become what you might call "pretty recognizable."